The present invention relates to an apparatus for advancing an object through a body passage comprising a radially expandable hollow member and an axially expandable hollow member connected to said radially expandable hollow member, said axially expandable hollow member designed such that it changes dimensions reversibly in its axial direction dependent on the pressure in the interior of the axially expandable hollow member, and a tube with a lumen for the supply and removal of inflation medium to the axially expandable hollow member.
The invention relates in particular to an intestinal probe for use in the evacuation of the intestinal waste from the gastro-intestinal canal.
Intestinal probes are useful e.g. in the treatment of early postoperative adhesion ileus (adhesions in the abdominal cavity), repeated late postoperative adhesion ileus, carcinomatosis peritonei (cancerous growth in the abdominal cavity), intestinal hematoma (hemorrhage in the abdominal cavity) in patients under anti-coagulation treatment and in the treatment of technically inoperable patients.
Prior art intestinal probes consist of a bladder mounted at the distal end of an aspiration tube provided with an additional lumen for the supply of inflation medium to the interior of the bladder.
In the treatment of the kind of disorders described above using the known intestinal probes, the probe is advanced through the nostril to the ventricle and out through the pylorus. The bladder is subsequently partially inflated with air and mercury, whereupon the gastric peristalsis in a gastrically healthy patient gradually and over a period of several hours, e.g. 6-10 hours, carries the intestinal probe all the way through the enteric system to the ileus site. In an ileus patient the intestinal probe advances considerably slower, because the intestinal functions is compromised by oedema in the intestinal lumen and the resulting fluid and electrolyte disturbances. In such cases it may take days before the bladder reaches the ileus-inflicted Intestinal regions.
When the bladder is positioned in an ileus-inflicted Intestinal region, a subatmospheric pressure is established in the aspiration conduit and the intestinal waste is evacuated from the intestine thereby establishing a normal intestinal peristalsis thus allowing the bladder to be carried on to other ileus-inflicted regions.
Whether a normal intestinal function can be reestablished with known intestinal probes depends on the etiology of the acute ileus condition.
In a number of cases the intestinal functioning of the distal end of an ileus-inflicted region is compromised to such an extent that evacuation of the intestines in the proximal area is not sufficient for the reestablishment of normal intestinal functions. In such cases the intestine is not capable of further advancing the intestinal probe and the desired effect of the treatment cannot be achieved.
In the known intestional probes the bladder serves to impart to the front part of the probe a diameter which is sufficient for the intestinal peristalsis to influence the intestinal probe and thereby advance it through the intestinal canal.
U.S. Pat. No. 4,176,662 discloses an endoscope having a propulsion mechanism consisting of two bladders and an axially expandable bellows separating said two bladders, and three different air tubes for selectively conducting inflation air to the bladders and the bellows. The propulsion mechanism is operated by initially supplying air to the proximal bladder while the bellows and the distal bladder are in their deflated condition. The supply is continued until the outside of the proximal bladder abuts the intestinal wall and thus secures the endoscope relative to the intestine. Air is subsequently supplied to the bellows thereby expanding it axially and provoking a propulsion of the front end of the endoscope. The distal bladder is then brought to expand until its outside abuts the intestinal wall and the front part of the endoscope is immobilized. A subsequent deflation of the proximal bladder and sequentially of the bellows, causes the bellows to contract and to pull the deflated proximal bladder and the tube onwards in the intestine. Following a final deflation of the distal bladder the cycle may be repeated.
As it appears from the above the functioning of the known propulsion mechanism is conditioned by the presence of three different air tubes and by careful control of the supply and evacuation of air through the tubes.